328i running hot

[FlogBimmerGnaw]

Hello all. I have an 09 328i and up until two days ago my thermostat has been right in the middle after warming up or a little below. Now it is right in the middle or a tiny bit above. When I say tiny I mean barely above the middle line. It's still worrying me and the car has been sitting for about 2 hours now and is still very warm. Can't check coolant level until tomorrow morning have to go to bed soon. Should I be concerned or am I freaking out for no reason? Ps it goes above the halfway mark when I'm accelerating fast but when I get to a red light it stops back in the middle and is fine if I drive normal. Should I stop driving like a dumb kid( I'm 24 very much a dumb kid) and racing every little 4 cylinder Honda that revs at me?

[Breeze1]

Hello all. I have an 09 328i and up until two days ago my thermostat has been right in the middle after warming up or a little below. Now it is right in the middle or a tiny bit above. When I say tiny I mean barely above the middle line. It's still worrying me and the car has been sitting for about 2 hours now and is still very warm. Can't check coolant level until tomorrow morning have to go to bed soon. Should I be concerned or am I freaking out for no reason? Ps it goes above the halfway mark when I'm accelerating fast but when I get to a red light it stops back in the middle and is fine if I drive normal. Should I stop driving like a dumb kid( I'm 24 very much a dumb kid) and racing every little 4 cylinder Honda that revs at me?

If the temp is higher than it used to be under the same conditions, it makes sense that something has gone wrong. It also makes sense that you stopped stepping on it until you figure out what the cause is... you probably have a cooling system issue.

[02Pilot]

Generally speaking, the gauge should be rock-steady in the middle once warmed up. That's because the temperature gauge is buffered, so as not to freak people out with small movements. It also doesn't offer any precise information. Put a scan tool on the car and monitor operating temps when running and report them here. But yes, you likely have a problem with the cooling system and you will need to address it if you want to avoid potentially inconvenient or possibly even catastrophic problems.

And yes, stop driving like a dumb kid...on the street. Racing is great, but keep it on the track.

[MarcoZandrini]

The water pump in your car is electric. I’m betting it’s going bad. If it is going bad you’ll need to replace it and the thermostat together.

Have you checked the coolant level. Read the owner’s manual to see how to check it.

[bmwdirtracer]

I'll bet the computers know what's going on. If you get the car connected to a good BMW specific diagnostic scan tool, you'll find out what they know.

[jclausen]

It's is my understanding that it does not have a coolant temperature gauge?

[bmwdirtracer]

Nope, another of those things, like a dipstick, that they thought we should live without. You might be able to pull up a special function in the cluster, I don't know. Personally, I just hook up a scan tool, and/or aim an infrared temp gun at the hoses. Still, the E90 sets codes for thermostat and water pump, always good to check.